Does having affiliates hurt seo?

[Ezpro9]

one of my clients has a TON of affiliates out there building links back to his site all with the ?ref=AFFILIATENAME tracking string

does google understand this and not count these links or is there a way to nofollow all links with this tracking string?

just wondering how big companies rank well and still have thousands of affiliates building links on all kinds of properties using all kinds of methods

thanks

[matbennett]

i doubt google could ever do anything about it because so many legit sites get 50%+ of their business from their affiliates

Bit of an over-estimation, but 2 years ago I would have agreed that they wouldn't do it.  Today I'm less sure.

[Ezpro9]

thanks mat

i doubt google could ever do anything about it because so many legit sites get 50%+ of their business from their affiliates - and seems like every website has a banner of some sort linking to another site as an affiliate so i think a large percentage of the actual internet is affiliate marketing based

im sure more sites exist for the sole purpose of making an affiliate buck than actual company sites - literally every blog makes money as an affiliate in some manner or another

but thanks for the answer - i will do the site: search now

[matbennett]

I don't believe that affiliate links in themselves cause issues on a technical level.  However lots of links with ref=affiliatename could potentially cause a canonicalisation issue is they have not been redirected properly.  A quick search to see if any have been indexed (site:sitename.com inurl:ref=) will tel you.

Assuming that is OK you should be fine.  It is worth remembering that you cannot nofollow incoming links anyway. You would need to get the sites to nofollow the links as it is done in the source of the link.

However... strictly speaking affiliate links are paid links.  Google rules state paid links should be nofollowed.  Affiliate links don't usually seem to be no-follow (even the aff networks don't add the nofollow attribute in the code they provide), however they probably should be.  Google could well crack down on this at some point.